Mathematics - Sequence & Series Question with Solution | TestHub

First term $=b$ and common ratio $=\mathrm{r}$ For infinite series, Sum $=\frac{b}{1-r}=5$ $\Rightarrow b=5(1-\mathrm{r})$ So, interval of $b=(0,10)$ as, $-1<\mathrm{r}<1$ for infinite GP.